Title : From bench to atmosphere: New materials for Direct Air Capture (DAC) of CO2 using electro-swing chemistry
Abstract:
The increased amount of carbon dioxide (CO2) in the atmosphere is the main factor contributing to recent climate change. This accumulation of CO2 is mainly due to the burning of fossil fuels that disrupts the natural carbon cycle. In addition to global warming, the abundance of atmospheric CO2 also causes ocean acidification, agriculture disruption, and negative impacts on human health. Recent studies determined that simply reducing emissions is insufficient to restore the Earth’s atmospheric system—negative emissions are now in dire need. Current carbon (i.e., CO2) capture technologies use thermo/pressure swing which often suffers from low energy efficiency, high cost, and geographic constraints. Electro-swing chemistry-based carbon capture using quinone sorbents emerged as a promising potential solution to these problems. However, strong CO2-binding sorbents, not susceptible to oxygen interference, remain elusive. In this study, I designed and synthesized three novel quinones for direct air capture (DAC) of CO2. Cyclic voltammetry studies of these quinones and follow-up data analysis found that 2,3-dicyanobenzoquinone (DBQ) has a second reductive potential of -0.935 V, positive of that of oxygen, and binds to CO2 strongly with the binding free energy ΔGbind of -5.39 kcal/mol. These results suggest that DBQ is a desired sorbent that can capture >70% of CO2 at low concentrations (i.e., 420 ppm in the current atmosphere) at room temperature using electro-swing chemistry without oxygen interference. This technology has the potential to be further developed for worldwide applications by solving global warming and its implications.
